Document EP-A-148 394 discloses an electrical link device for a metal-clad unit, where the device is insulated by means of a fluid such as sulfur hexafluoride in gaseous form. The electrical link device described in that document has a conductive link bar placed inside the enclosure with one end fixed in leakproof manner to a sleeve of insulating resin that passes in leakproof manner through the wall of the enclosure that contains the insulating gas. The link bar extends outside the enclosure and is connected to a pluggable connection member disposed in the portion of the sleeve that extends outside the enclosure and that is surrounded by a conductive screen forming a Faraday cage around the pluggable connection member.
Such an electrical link device is the seat of high levels of electric stress when it is used at very high voltage. In addition, since that device does not have any electric field-distributing member, it is necessary to provide a separate stress-reducing member which is mounted on the electricity cable prior to it being put into position, thus requiring manipulation to be performed to avoid electric stresses appearing at the interface between the inside surface of the insulating sleeve and the field-distributing member, which manipulations are difficult to perform on site.